Patent GB-190608502-A (GB)
Title: Improvements in Driving and Steering Mechanism for Motor Vehicles.
Inventor: MEDVECZKY EDWARD
Filed: 1906-04-09
Granted: 1906-11-29
Abstract: 8502. Medveczky, E. April 9. Variable-speed and reversing gearing; lever linkages.-Relates to the construction and control of continuously variable change-speed gear for motorvehicles in which the rear driving-wheels are driven independently, and provides means in connexion with the steering-gear for driving the wheels at different speeds when the vehicle is turning. A form of reversing-gear is also described. Fig. 2 shows the general arrangement of the vehicle in plan, Figs. 3, 5, and 14 are detail views of the controlling pedals and mechanism, and Figs. 8, 9, and 12 are elevations of the rear axle driving-mechanism. The motor shaft 1 drives by means of bevel-gearing a countershaft 4, on which are mounted independently two eccentrics 5, 5<1> of adjustable throw. These eccentrics drive the rear axle through friction ratchet mechanism, operated by the rods 26, 27, and 28. The throw of each ecccentric is adjusted by means of a rack formed on a sleeve 6, which is adapted to rotate a toothed segment 7 engaging another rack formed on the eccentric bush. The sleeve 6 rotates with the shaft on which it is mounted, and its longitudinal movement is effected by a non-rotary sleeve 11, actuated by a pivoted fork-ended lever 12, the other end of which is operated by a spiral cam 13, formed on a sleeve 15, mounted on a spindle 14. This spindle is rotated in one direction by a pedal 22 carrying a toothed sector 19 engaging a pinion 17, and in the other direction by another pedal 23 which carries a toothed sector engaging the underside of a pinion on the spindle. The throw of the eccentrics, and thereby the speed of the vehicle, is increased or diminished by the downward movement of the pedals 22, 23, respectively. In order to obtain different speeds for the two rear wheels on rounding a curve, the sleeve 15 is adapted to be moved along the spindle 14 by the steering-gear. Fig. 14 is a detail view showing the link-work for effecting this. A pin on the. end of a lever 64, pivoted at 73, engages a groove in the sleeve 15. The other end of this lever is slotted to receive a pin 63, by means of which it is connected to a second slotted lever 65, which is hinged to a link 67 engaging a cam-groove in a plate fixed to the steering-spindle. The pin 63 is moved along its slots by a rod 62, operated by a rack 60 engaging a pinion on the spindle 14. The effect of this linkwork is that the ratio of the speeds of the driving- wheels consequent upon a given movement of the steering-post is dependent on the speed of the vehicle. The friction ratchet driving-mechanism and the reversing-gear fitted on the rear axle are shown in Figs. 8, 9, and 12. The connecting- rods 27, 28 are, respectively, hinged to pins 30, 31 on the disks 32, 33, which are connected by hinged links 41, 42 to friction blocks 40, 39. These blocks slide in radial guides 34, 36, and are adapted to engage alternately with the inner wall of the drum 43, so as to produce a continuous rotary motion. An extension of the drum 43 is provided with internal teeth meshing with a pinion 45, mounted in a carrier 48 and engaging a central wheel 46. For forward driving, the carrier is held fixed by a clutch sleeve 50, which is slotted to engage a pin 51 on the carrier and is itself held by the teeth 53, the shaft being driven at an increased speed, and in the opposite direction to the drum 43. For reverse driving, the clutch 50 is moved to the left by the pin 56, thereby locking the wheel 46 to the carrier, the shaft being rotated at the same speed and in the same direction as the drum 43.